A minor fourteen or fifteen years of age may not be employed or permitted to work in any occupation except farm labor, domestic service, or in the employment of, and under the direct supervision of, the minor’s parent or guardian unless the minor is exempt from compulsory school attendance under subdivisions b, c, and d of subsection 1 of section 15.1-20-02 or unless the minor has an employment certificate signed by the minor’s parent or guardian in accordance with the provisions of this chapter. Any person, firm, corporation, or limited liability company employing a minor must keep on file a completed employment certificate, for each minor, as provided in this chapter. The employment certificate must be accessible to inspection by the principal of the school which the minor attends, a principal in the municipality in which the minor resides, or the labor commissioner or the commissioner’s agent or representative.